This application is to purchase a new cell sorter to replace an existing, older sorter which is no longer reliable, cannot be upgraded to current standards, and cannot perform a number of requirements of current users. Over the past 14 years Purdue University has maintained a cell sorter operation. In 1986 an Epics 752 was purchased under an NIH shared instrumentation grant. This instrument was taken completely out of service in 1994. In 1990, under an agreement with the manufacturer, we obtained a prototype Epics Elite sorter which has served this facility well over the past 9 years. Because this instrument was not a full production model, there are certain aspects to the instrument that are not standard. In addition, the instrument is close to reaching the end of its useful life and, with added demands upon the sorting aspects of flow cytometry at our institution, we believe it is time to replace this instrument with an instrument that can accommodate our user's needs. In this regard the instrument proposed has been designed to perform not only high speed sorts, but rapid set-up sort sessions, an excellent single cell plate deposition unit ranging from 12-384 well plates, and all of the laser combinations we currently require or &e likely to need with current and future users over the next several years. The facility has a long track record of shared use of our high technology instruments. The resource in which they are operated has a rich history of not only providing resources to NIH investigators at this institution, but also knowledge and educational resources to those at institutions all over the country. The instrument requested will provide a much needed upgrade to our resource providing NIH funded investigators with the high quality tools necessary to produce quality science.